timing marks

[DixIndian]

we are tearing the engine down and are at the timing gears. there should be 2 marks, one on each gear to set the chain. the cam gear has a small circle but the crank gear has nothing. the manual shows a mark on each. this is new to me because my antique motorcycles have meshing gears and the 2 marks are easy to mate.  this has the chain and there is huge slop in the chain (will replace). we need to be sure the 2 are in sync. any ideas are appreciated.Thanks
Richard